Creating tables that are based on data from different data sources Sometimes—for example, when creating a bridge table—you may need to extract distinct values from more than one table because the distinct values may be different in different tables. In that case, you’d need to take distinct values from both tables, and if they come […]
Create hierarchies Power BI allows you to group columns into hierarchies, which you can then use in visuals. In our Wide World Importers example, you can create a geographical hierarchy as follows: Go to the Model view. Right-click the Sales Territory column in the City table. Select Create hierarchy. Double-click the newly created hierarchy and […]
Create calculated columns Calculated columns are columns you create by using DAX. Similar to calculated tables, calculated columns can only use the data already loaded into the model or new data generated by DAX, and they don’t appear in Power Query Editor because they are generated after the data has been loaded into the model. […]
Implement row-level security roles A common business requirement is to secure data so that different users who view the same report can see different subsets of data. In Power BI, this can be accomplished with the feature called row-level security (RLS). Row-level security restricts data by filtering it at the row level, depending on the […]
Viewing as roles in Power BI Desktop In Power BI Desktop, you can check what the users with specific roles will see even before you publish your report to the Power BI service and assign users to roles. For this, once you have at least one role defined, select View as on the Modeling ribbon […]
Dynamic row-level security The roles we’ve created so far have been static, which means that all users within a role will see the same data. If you have many rules that specify how you should secure your data, this approach may mean you have to create a number of roles as well as update the […]
Cross filter direction This option determines the direction in which filters flow. For many-to-one and one-to-many relationships, you can select Single or Both: When editing table relationships, even if you set the relationship cross-filter direction to Both, by default the security filters are only applied in one direction. We noted that there’s an option to […]
Use the Q&A feature Both Power BI Desktop and the Power BI service allow you to create visualizations that provide answers to specific questions. Although this gives you great control over formatting, it won’t work if you have RLS set up and users only have read access to content. Another way to explore data in […]
Teach Q&A The Q&A visual didn’t understand the term units because it doesn’t appear in the Wide World Importers data model. The Q&A visual underlines in red the terms it doesn’t understand. If you select units in the Q&A visual, you may be given suggestions to replace units with another term or to define the […]
Skill 2.3: Create model calculations by using DAX You used some DAX earlier in the chapter to create calculated tables and calculated columns as well as configure row-level security. In practice, DAX is most often used to create measures in Power BI. Writing your own formulas is an important skill that allows you to perform […]
